To attain maximum efficiency from an ice skate, it is important that both edges of a skate's blade are square to the side of the blade along the entire length of the blade. The edges serve as both accelerator and brakes, and if the edges are not completely square to the blade, the skater will not be able to skate at full speed and stop in the shortest distance. The skater will be also prone to overcompensating weight distribution in turns, and is more likely to fall. Using the present invention, a sharpening professional or consumer can see if both edges are precisely at a 90 degree angle to the side of the skate's blade along the entire length of the blade.
There is known U.S. Pat. No. 5,345,688 relating to a method and device for measuring squareness of ice skate blades comprising a clamped-on squaring body and a magnetically-attachable angle. However, this instrument has several disadvantages: it is expensive to manufacture, it cannot be slid along the blade to get a continuous reading of the entire blade, the sharpener must remove the skate from its sliding carriage in order to attach this instrument, the clamp cannot be effectively attached to worn-down blades, the threads on the bolt portion of the clamp wear out, and the clamp portion tends to develop a bevel after prolonged use thus making the instrument provide false readings.
There is also known U.S. Pat. No. 6,481,113 comprising a clamp and an indicator arm. This invention suffers from the same defects as U.S. Pat. No. 5,345,688.